Overview

Definition:
-Rheumatic fever (RF) is an acute, inflammatory, non-suppurative, multi-systemic illness that may develop as a delayed sequela of Group A beta-hemolytic streptococcal (GABHS) pharyngitis
-It is characterized by a spectrum of manifestations affecting the heart, joints, brain, skin, and subcutaneous tissues.
Epidemiology:
-While declining in incidence in developed countries, RF remains a significant public health problem globally, particularly in low- and middle-income countries
-It typically affects children and adolescents aged 5-15 years
-Recurrences are common and contribute to the development of chronic rheumatic heart disease (RHD).
Clinical Significance:
-RF is a leading cause of acquired heart disease in children and young adults worldwide
-Untreated or inadequately treated RF can lead to irreversible valvular damage (rheumatic heart disease), resulting in significant morbidity and mortality
-Early diagnosis and appropriate management, including secondary prophylaxis, are crucial to prevent cardiac sequelae.

Clinical Presentation

Symptoms:
-Fever
-Joint pain and swelling, typically migratory and affecting large joints (arthritis)
-Abdominal pain
-Nausea and vomiting
-Shortness of breath or chest pain (suggesting carditis)
-Involuntary purposeless movements of the limbs, face, or trunk (chorea)
-Skin rash, often a faint, non-itchy, pink rash with irregular, spreading edges (erythema marginatum)
-Small, painless lumps under the skin, typically over bony prominences (subcutaneous nodules).
Signs:
-Tachycardia and possibly murmurs or rubs on cardiac auscultation (suggesting carditis)
-Tender, swollen, and warm joints with limited range of motion (arthritis)
-Petechiae, purpura, or pallor
-Specific neurological signs with chorea (e.g., "milkmaid's grip," facial grimacing)
-Characteristic erythematous or nodular skin lesions.
Diagnostic Criteria:
-The modified Jones criteria are used for diagnosis
-Diagnosis requires evidence of a preceding GABHS infection (positive throat culture, rapid antigen detection test, or elevated anti-streptococcal antibody titers like ASO or anti-DNase B) plus either: 1) two major criteria, or 2) one major criterion and two minor criteria
-Major criteria: Carditis, Polyarthritis, Chorea, Erythema Marginatum, Subcutaneous Nodules
-Minor criteria: Fever, Arthralgia, Elevated acute phase reactants (ESR, CRP), Prolonged PR interval on ECG.

Diagnostic Approach

History Taking:
-Detailed history of recent sore throat or scarlet fever
-Any history of recurrent pharyngitis
-Family history of rheumatic fever or rheumatic heart disease
-Onset and progression of symptoms, particularly migratory joint pain, chest pain, shortness of breath, or neurological changes
-Recent travel to endemic areas
-Immunization status.
Physical Examination:
-Thorough cardiac examination including auscultation for murmurs (new or changing), rubs, and gallops
-assessment for cardiomegaly
-Examination of joints for signs of inflammation (swelling, tenderness, erythema, warmth)
-Neurological examination focusing on motor coordination and presence of choreiform movements
-Skin inspection for erythema marginatum or subcutaneous nodules
-Palpation of lymph nodes.
Investigations:
-Throat swab for culture and sensitivity to rule out residual GABHS infection
-Antistreptococcal antibody titers: Anti-streptolysin O (ASO) and Anti-DNase B are most useful for confirming recent infection, especially if the throat culture is negative
-A single elevated titer is suggestive
-a rising titer over 2-3 weeks is more definitive
-Electrocardiogram (ECG) to assess for PR prolongation and other signs of carditis
-Echocardiography to evaluate for valvular involvement (regurgitation, stenosis), pericardial effusion, and myocardial dysfunction, especially in suspected carditis
-Complete blood count (CBC) to assess for leukocytosis and anemia of chronic disease
-Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) for evidence of inflammation
-Chest X-ray if significant respiratory symptoms are present.
Differential Diagnosis:
-Reactive arthritis (post-infectious arthritis)
-Other causes of arthritis in children (e.g., juvenile idiopathic arthritis, septic arthritis, viral arthritis)
-Other causes of chorea (e.g., Huntington's disease, Wilson's disease, systemic lupus erythematosus)
-Viral pericarditis
-Kawaski disease (shares some features but typically presents with different constellation of symptoms and signs, especially conjunctivitis and lymphadenopathy)
-Psoriatic arthritis
-Leukemia.

Management

Initial Management:
-Hospitalization is recommended for patients with carditis, severe arthritis, chorea, or those unable to manage at home
-Rest is crucial, especially with carditis
-Eradication of any residual GABHS infection with antibiotics (e.g., Penicillin G benzathine IM or oral penicillin V for 10 days).
Medical Management:
-Anti-inflammatory therapy: Salicylates (aspirin) are the mainstay for arthritis and carditis
-Dosage typically 60-100 mg/kg/day divided into 4-5 doses, with the dose adjusted to achieve symptomatic relief and an ESR < 20 mm/hr
-For severe carditis with heart failure, corticosteroids (e.g., prednisone 1-2 mg/kg/day) may be used cautiously, usually followed by salicylates
-Aspirin is continued until symptoms subside and inflammatory markers normalize
-Chorea may require specific management with sedatives (e.g., benzodiazepines) or anticonvulsants (e.g., valproate, haloperidol in severe cases) if significant, and is usually self-limiting over weeks to months.
Surgical Management:
-Not typically required in the acute phase of rheumatic fever
-Surgical intervention (e.g., valve repair or replacement) is reserved for managing the chronic sequelae of rheumatic heart disease (valvular stenosis or regurgitation) that develop years later.
Supportive Care:
-Nutritional support
-Psychological support for patients and families, especially with chorea
-Monitoring of vital signs, cardiac function, and neurological status
-Patient education regarding the importance of adherence to secondary prophylaxis.

Complications

Early Complications:
-Carditis with heart failure, myocarditis, pericarditis
-Severe polyarthritis causing significant pain and immobility
-Acute rheumatic encephalopathy (sydenham chorea).
Late Complications:
-Chronic rheumatic heart disease (RHD) due to progressive valvular damage, most commonly affecting the mitral and aortic valves, leading to stenosis and/or regurgitation
-This can result in atrial fibrillation, pulmonary hypertension, infective endocarditis, and heart failure
-Recurrent episodes of RF can exacerbate valvular damage and hasten the onset of RHD.
Prevention Strategies:
-Primary prophylaxis: prompt and adequate treatment of streptococcal pharyngitis/scarlet fever with antibiotics to prevent the initial episode of RF
-Secondary prophylaxis: continuous antibiotic therapy (usually long-acting benzathine penicillin G IM every 3-4 weeks) to prevent recurrent GABHS infections and subsequent episodes of RF and progression of RHD
-Duration of prophylaxis depends on the severity of the initial illness, presence of carditis, and residual RHD.

Secondary Prophylaxis

Rationale: To prevent GABHS recurrences, which can lead to new or progressive valve damage and chronic rheumatic heart disease.
Duration And Regimen:
-Duration varies based on severity: 1) No carditis: 5 years or until age 21, whichever is longer
-2) Carditis, no residual valve disease: 10 years or until age 21, whichever is longer
-3) Carditis with residual valve disease: 10 years or until age 21, whichever is longer, often lifelong
-Long-acting benzathine penicillin G 1.2 million units IM every 3-4 weeks for adults/adolescents, or 600,000 units for children < 27 kg
-Alternatives include oral penicillin V or macrolides for penicillin-allergic patients (with careful consideration of cross-reactivity and compliance).
Compliance And Monitoring:
-Strict adherence is paramount
-Regular follow-up is essential for monitoring compliance, assessing for breakthrough infections, and clinical/echocardiographic evaluation for progression of RHD
-Education of patient and family on the lifelong importance of prophylaxis.

Key Points

Exam Focus:
-Jones criteria (major/minor), definition of carditis, arthritis, chorea, erythema marginatum, subcutaneous nodules
-Diagnostic value of ASO and Anti-DNase B titers
-Primary vs
-Secondary prophylaxis distinction
-Regimens for secondary prophylaxis (Benzathine Penicillin G)
-RHD as the major long-term complication.
Clinical Pearls:
-Migratory arthritis is a hallmark of RF
-Chorea can be the sole manifestation, appearing weeks or months after the initial infection
-Echocardiography is essential to assess for subclinical carditis
-Secondary prophylaxis is a critical component of long-term management and requires patient education and strict adherence.
Common Mistakes:
-Inadequate treatment of streptococcal pharyngitis (leading to primary RF)
-Discontinuation of secondary prophylaxis too early
-Misinterpreting minor criteria as major or vice versa when applying Jones criteria
-Failing to consider RF in children with unexplained arthritis, chorea, or cardiac symptoms.